Exposing Fields of Filth: Data and Methodology

Data provided on the maps represent estimations of locations and statistics in an attempt to accurately document animal feeding operations and their impact on the landscape. EWG and Waterkeeper Alliance assume no responsibility for locational accuracy, errors or omissions represented on the maps.

Animal Feeding Operation Map Attributes

County: North Carolina county in which animal feeding operation exists.

Operation: “FACILITY NAME” from N.C. Department of Environmental Quality List of Permitted Animal Facilities (January 2015) for all cattle and swine operations. For various poultry operations “OWNNAME” was attributed to the location from the N.C. Parcel Boundaries (June 2013).

Hogs and Pigs: Aggregate animal count from “ALLOWABLE COUNT” of the N.C. Department of Environmental Quality List of Permitted Animal Facilities (January 2015) within the county boundary.

Poultry: Aggregate animal count from Poultry - Inventory and Sales USDA AG Census 2007 and 2012 within the county boundary.

Cattle and Calves: Aggregate animal count from “ALLOWABLE COUNT” of the N.C. Department of Environmental Quality List of Permitted Animal Facilities (January 2015) within the county boundary.

Poultry Barns: Aggregate count of poultry barns visible at the location from Waterkeeper Alliance within the county boundary.

Waste Lagoons: Aggregate count of waste lagoons operations within the county boundary.

Animal Feeding Operations: Aggregate count of animal feeding operations within the county boundary.

Block Map Attributes

Total Population: The total population within the block boundary. Data estimates from the 2010 U.S. Census and various U.S. Census surveys.

Percent African American: The percent of African Americans within the total population of the block boundary. Data estimates from the 2010 U.S. Census and various U.S. Census surveys.

Percent Native American: The percent of American Indian and Alaska Native within the total population of the block boundary. Data estimates from the 2010 U.S. Census and various U.S. Census surveys.

Percent Hispanic (any race): The percent of Hispanic (any race) within the total population of the block boundary. Data estimates from the 2010 U.S. Census and various U.S. Census surveys.

Percent Under 18: The percent of individuals under the age of 18 within the total population of the block boundary. Data estimates from the 2010 U.S. Census and various U.S. Census surveys.

Percent Living in Poverty: The percent of individuals living below the poverty line within the total population of the block boundary. Data estimates from the 2010 U.S. Census and various U.S. Census surveys.

Waste Lagoons - Data representing the perimeter measurements of waste lagoons were compiled by EWG. Lagoons polygons were heads-up digitized using 2014 USDA NAIP aerial photography. The North Carolina Department of Environment and Natural Resources Division of Water Quality Swine Lagoon point layer served as a proxy for known swine lagoons. Visible lagoons on aerial photography not marked with the N.C. point layer were also capture and classified as unknown.

Waste Estimate Methodology

Poultry Waste Estimates

To calculate the poultry waste universe, EWG took the highest county-level estimates found in the USDA Agricultural Census between 2007 and 2012 for “Pullet”, “Turkey”, “Layer” and “Broiler.” Those county-level numbers were then evenly distributed by the number of poultry barns associated within an individual operation, within the county for each poultry category (as documented by Waterkeeper Alliance). Manure outputs were calculated using the specific poultry type and count from the 2016 North Carolina Agricultural Chemicals Manual, specifically Chapter IV-Fertilizer Use, page 62, “Livestock & Poultry Manure Production Rates and Nutrient Content” (see Figure 1 below).

Figure 1- Manure Volume and Weight in Typical North Carolina Animal Production Systems

Swine Waste Estimates

To calculate the swine waste universe, EWG used permit data from the North Carolina Department of Environmental Quality to determine animal type and count. Manure outputs were calculated using the specific type and count from the 2016 North Carolina Agricultural Chemicals Manual, specifically Chapter IV-Fertilizer Use, page 62, "Livestock & Poultry Manure Production Rates and Nutrient Content." For animal types that did not appear on the 2016 North Carolina Agricultural Chemicals Manual, EWG used manure metrics for a similar type of animal. This was done for Swine - Boar/Stud, Swine – Gilts, and Swine – Other (see Figure 2 below).

Cattle Waste Estimates

To calculate the cattle waste universe, EWG used the permit data from the North Carolina Department of Environmental Quality to determine animal type and count. EWG Manure outputs were calculated using the specific type and count from the 2016 North Carolina Agricultural Chemicals Manual, specifically Chapter IV-Fertilizer Use, page 62, “Livestock & Poultry Manure Production Rates and Nutrient Content.” For animal types that did not appear on the 2016 North Carolina Agricultural Chemicals Manual, EWG used manure metrics for a similar type of animal. This was done for Cattle - Dry Cow (see Figure 3 below).